Beemann



NlTE STATES PATENT OFFIQE.

CARL THEODOR LIEBERMANN, OF BERLIN, AND FRITZ GIESEL, OF BRUNSYVICK, GERMANY.

PROCESS OF OBTAINING ECGONINE.

SPECIFICATIQN forming part of Letters Patent No. 450,887, dated April 21, 1891.

Application filed September 18, 1888. Serial No. 285,716- (No specimens.) Patented in Germany August 14, 1888, No. 47,602.

To all whom it may concern:

Be it known that we, CARL Tnnonon LIE- BERMANN, a subject of the King of Prussia, residing" "at the city of Berlin, Prussia, Germany, and FRITZ GIESEL, a subject of the King of Prussia, residing at the city of Brunswick, Germany, have invented certain new and use ful Improvements in Processes of Conversion of the Amorphous Alkaloids of Coca-Leaves into Ecgonine and Benzoyl Ecgonine, (for which we have obtained Letters Patent in Germany, No. 7,602, dated August l i, 1888,) of which the following is a specification.

It is well known that the coca-leaves contain besides cocaine considerable quantities of amorphous alkaloids, which impair the physiological effect of cocaine an d which have to be separated from the same or from the crude cocaine before it can be applied to therapeutical treatment. These amorphous alkaloids may be separated by solution and orystallizing out the cocaine, and they form the subject-matter of our invention.

The following method gives very satisfactory results: The coca-leaves are moistened with a twenty-percent. solution of soda and extracted by ether, which dissolves the cocaine and its amorphous alkaloids. By thoroughly shaking the ether with diluted muriatic acid the amorphous alkaloids are extracted and obtained in aqueous solution, from which they are precipitated by adding soda. The precipitate corresponds to the crude commercial cocaine in the market, and contains, according to the kind and quantity of the leaves employed, besides cocaine, varying quantities of amorphous alkaloids. By dissolving this pre cipitate-respectively the crude cocaine heating it with a small quantity of alcohol, and permitting the solution to cool and stand for some time the cocaine crystallizes from the solution, while the amorphous alkaloids remain in solution and are obtained by the evaporation of the alcohol.

The method described, as well as othersimilar methods which were employed for producing cocaine from the coca-leaves or crude cocaine, furnish as a by-product the amorphous alkaloids referred to, which were not utilized, constituted to some extent a loss or waste of cocaine. These amorphous alkaloids of cocaine can, however, be utilized by our process, as by decomposing them ecgonine can be readily obtained from said alkaloids, which ecgonine can be converted intobenzoyl-ecgonine, from which, by well-known methods, cocaine can be produced, so that by our process cocaine can be produced in a comparatively easy manner from by-products which heretofore had to go to waste.

In the preparation of ecgonine from the amorphous alkaloids of the coca-leaves the amorphous-alkaloids of cocaine readily undergo a reaction, by which they decompose int-o organic acids and ecgonine, mostof them with a simultaneous formation of methyl-alcohol. This decomposition may be eifected by acids or alkalies and alkaline earths and partially andinsufficientlybysuperheatedsteam. Ve prefer to decompose the amorphous alkaloids by boiling them with hydrochloric acid. The concentration or the quantity of this acid is of little importance; but we prefer to use hydrochloric acid of 1.1 to 1.2 specific gravity, which is used in excess. On the concentration of the acid and the relative quantity of the same depends the time in which the reaction is complete, which takes usually from one to two hours oreven a shortertime. The insoluble organic acids formed are, after cooling, filtered oif, and the filtered liquor containing thehydrochlorate of ecgonine is evaporated to dryness. The remaining, salt, washed with a small quantity of alcohol, is nearlypure hydrochl'orate of ecg'onine, from which the free base is obtained by adding an alkali or alkali carbonate. The ecgonine thus obtained may, if necessary, be purified by crystallization in alcohol. Ecgonine is readily converted into henzoyl-ccgonine, and for this purpose either chloride of benzoyl or benzoic anhydride and dry ecgonine or ecgonine with a smaller quantity of water may be employed.

\Ve herewith give an example of benzoylating ecgonine; but we do not wish to confine ourselves either to the use of benzoic anhydride only, as other substances-for instance, chloride of benzoylgi\'e the same result; nor to the exact quantities and details, for the reason that larger quantities of benzoic anhydride or the exclusion of water gives satisfactory results.

.An aqueous solution of ccgonine (one molecule) saturated at boiling-heat is added to an equivalent quantity of benzoic anhydride, (one molecule.) To complete the reaction we heat the mixture for a short time (about one-half to one hour) to the boiling-point. To remove the benzoic acid produced, the product of the reaction is, after cooling, repeatedly shaken or agitated with ether. The remaining aqueous solution begins to solidify to a crystalline mass, either immediately after shaking or after standing for some time. The crystals are separated from the mother-liquor by means of a pump and washed with a small quantity of water. They consist of benzoyl-ecgonine, which is identical with and has all its properties with the benzoyl-ecgonine heretofore known. The mother-liquor contains some ecgonine which has escaped the process of benzoylation. This liquor may be used directly for other benzoylating operations, or the ecgonine may be regained from it by any known process. The benzoyl-ecgonine thus obtained is then converted into cocaine by any well-known meth- 0d, and is thus obtained from its worthless by-product-s contained in the coca-leaves.

Having thus described our invention, we claim as new and desire to secure by Letters Patent 1. The process herein described of producing ecgonine from the amorphous alkalolds contained in the coca-leaves or in crude cocaine, said process consistingin decomposing the amorphous alkaloids by a suitable medium into organic acids and ecgonine, separating the organic acids by filtration from the solution, evaporating the latter, and crystallizing the ecgonine from the residue by means of alcohol, substantially as set forth.

2. The process herein described of treating the amorphous residues from the manufacture of cocaine, which consists in the decomposing said amorphous alkaloids by a suitble medium into organic acids and ecgonine, separating the ecgoni'ne from its solution, and converting it by treatment with 'benzoyl or benzoic anhydride into benzoyl-ecgonine, substantially as set forth.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

CARL THEODOR LIEBERMANN. FRITZ GIESEL.

Witnesses:

B. R01, GAsPER VoGT. 

